Related Experiment Video
Updated: Apr 5, 2026
En Face Endocardial Cushion Preparation for Planar Morphogenesis Analysis in Mouse Embryos
Published on: July 27, 2022
3-D reconstruction and multiple marker analysis of mouse proepicardial endothelial cell population
Justyna Niderla-Bielińska1, Grzegorz Gula2, Aleksandra Flaht-Zabost3
1Department of Histology and Embryology, Medical University of Warsaw, Poland.
Background:
The proepicardium (PE), a transient embryonic structure crucial for the development of the epicardium and heart, contains its own population of endothelial cells (ECs). The aim of our study was to determine the pattern, anatomical orientation and phenotypic marker expression of the endothelial cell network within the PE.
Results:
Immunohistochemical findings revealed that proepicardial ECs express both early and late EC-specific markers such as CD31, Flk-1, Lyve-1 and Tie-2 but not SCL/Tal1, vWF, Dll4 or Notch1. Proepicardial ECs are present in the vicinity of the sinus venosus (SV) and form a continuous network of vascular sprouts/tubules connected with the SV endothelium, with Ter-119-positive erythroblasts in the vascular lumina.
Conclusions:
On the basis of our results, we postulate the existence of a continuous network of ECs in the PE, exhibiting connection and/or patency with the SV and forming vessels/tubules/strands. Marker expression suggests that ECs are immature and undifferentiated, which was also confirmed with a transmission electron microscopy (TEM) analysis. Our results deliver new data for a better understanding of the nature of proepicardial ECs.
